Giant TCX SLR frame: Cable routing overview

Home mechanics may balk at two features more frequently appearing in bikes: a press-fit bottom bracket shell, and internal cable routing.

Regarding the former, I had a little trepidation with the risks of a press-fit bottom bracket system on my 2014 Giant TCX SLR 2. Naysayers complain about the potential for creaks and bearing cups walking themselves out of the frame. It turns out I need not have worried. In my two years with the bike, I haven’t had any real problems with BB86 – apart from the prohibitive prices of relevant tools.

DIY cable replacement on the TCX, on the other hand…


First, let’s go over everything you’ll need for this job. Let’s start with the cables.

2100 mm worth of Shimano’s shift inner cable.

Anything from Shimano, SRAM or Jagwire should suffice, as far as shift inner cables are concerned. More expensive cables sport a coating for reduced friction within the cable housing, or outer cable.

When it comes to shift cable housing, many mechanics swear by Shimano’s SP-41. It’s cheap, and it just works beautifully. Jagwire makes its own LEX shift outer cables as well; since it’s what my bike came with, I can say it’s pretty good too.

It’s a similar story with brake inner cables: anything should suffice. What I would recommend, though, is to shoot for compressionless brake cable housing. TRP themselves recommend it for maximum performance out of their Spyre disc brake calipers.

Jagwire Road Pro DIY cable kit and Park Tool CN-10 cable cutters. Good cable kit, but you will need the extra length of the “XL” version for a cyclocross bike.

As far as cables go, I would suggest avoiding pre-cut cable kits on the TCX, unless they’re specifically meant for bikes that require full-length housing. It’s better to have more inner cable and housing on hand than what you need, instead of too little.

While we’re talking about supplies, don’t forget about cable end caps and ferrules. The latter prevent the inner cables from mushrooming inside their housings; the former prevent the sharp, exposed ends of inner cables from stabbing you. You may also want to take the opportunity to replace your handlebar tape, since removal is required to access the cables.

Finally, you’ll need some cable cutters – and it’s highly recommended that you get yourself purpose-made items. These will stay sharp and actually cut through inner cables and housing, instead of crushing them. I got myself Park Tool’s CN-10 cable cutters.

You may also want to employ some other tools, like long-nose pliers, a flashlight for peeking through the routing holes, and side cutters. If you’re running conventional spiral-wound brake cable housing, side cutters will do a slightly better job of cutting that to size.


Cable routing at the fork and downtube of the TCX. Note the in-line cable adjusters.

Around the handlebar area, cable routing on the TCX is identical to any contemporary road bike.

The front brake is simplest: all the cable is run externally. The bottom edge of the fork crown has a little retaining clip that holds the cable housing close to the fork. If you run fenders, you will have to remove them first to loosen the little bolt that holds this clip.

The three remaining cables have their own in-line barrel adjusters before eventually feeding into the downtube.

You’ll notice that there are a couple of holes. The one on the non-drive side contains a lone cable, and that’s for the rear brake. Both derailleur cables feed into the central hole.

The shift and rear brake cables exit the downtube around the bottom bracket shell through holes with rubber grommets. The two cables coming out of the left hole are for derailleurs. The lone cable on the right hole is for the rear brake.
The underside of the TCX’s bottom bracket shell. Top cable with the ferrule going into the chainstay grommet is for the rear derailleur. Middle cable is for the front derailleur. Bottom cable is for the rear brake – note the absence of ferrules. Removing the grommets exposes the full cable routing holes.

The rear brake cable housing is a full-length run, reappearing around the bottom bracket area, then going under again until eventually it pops out of the inboard side of the non-driveside chainstay. From here it’s a short distance away from the disc brake caliper, where it ends at the barrel adjuster.

Both derailleur cables pop out at the bottom bracket shell. The middle run is for the front derailleur, where the housing meets a cable stop behind the seat tube.

The remaining run of shift cable housing dips into a hole underneath the drive-side chainstay where it terminates in a ferrule. Once the inner cable gets out of the housing, it goes into a special liner that Giant runs through the length of the drive-side chainstay.

Close to the bottom bracket shell, there is an internal U-shaped hook that keeps this liner in place…or at least is supposed to. The other end is a round “cable stop” port that is seated at the dropout, preventing the liner from getting lost inside the chainstay. Pull this port, and you can pull out the entire internal liner.

The round hole is the anchor port of Giant’s internal liner that routes the shift inner cable through the chainstay. Pull this anchor port, and you can pull out the whole internal liner.

From there, it’s standard road bike shift cable routing. Ferrules at both ends, a second piece of cable housing connects the cable routing hole at the drive-side dropout and the rear derailleur’s barrel adjuster.

In the next post I’ll talk about the process of replacing a rear shift cable, since it’s one of the most involved maintenance processes on this generation of TCX.


3 thoughts on “Giant TCX SLR frame: Cable routing overview

  1. Thanks. This was really helpful. I’ve changed this out a couple of times, but never had any idea that that whole sleeve could come out, although I’ll have to check mine again, as I have the TCX SLR frameset which has a different fork, but I think the rest should be the same. I’m in the process of installing a Di2 system to replace the mechanical drivetrain, so right now the only thing I am a little worried about is exiting the rear derailleur Di2 cable on the chainstay. Entering I think should be straightforward, as it will be done from within the BB shell, and I think I can just plug or tape up the ports on the drivetrain side, as both the cables for the FD and RD will be internal with the b-junction box up there. I’ll have to take some pictures, as these DIY guides that people post are very helpful when there are no technical manuals available. Thanks again for posting.

    Liked by 1 person

    1. You’re welcome, and I’m glad it was useful.

      Regarding running the Di2 cable through the chainstay – there are many methods of doing it, although I think the Park Tool IR-1/IR-1.2 internal routing kit tools are the best way of doing so. Those have dedicated routing wires that will hold on to the end of an E-Tube Di2 cable, and then you can simply pull them along via the supplied guide magnets.

      I would love to see your work and how you get on with the job.


  2. I just ordered the Park cable Tool as I figure after a couple of installations it will have paid for itself. I have a Giant TCR which is all internally cabled as well. A bunch of the parts arrived yesterday, and the rest should be in mid-March, so I’m hoping to start the project shortly thereafter.


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